Launch new product vs revamping an older one (from LinkedIn Q&A)

A tough and profound decision. The key factors in play are:

1. Industry characteristics (some industries are notoriously slow to adopt a new product)
2. Product brand (has the product been branded? Is there a platform brand it rides on? Does the brand hold good equity with customers?)
3. Related to 2 (above) but different - are you targeting another different segment of the market with this product - a segment that values different features / characteristics? If so, it may be better to launch a new product - with completely differentiated value proposition.
4. What extra investment will the new launch take above and beyond the revamped product?

Some examples:
Example 1: Product A has been in the market and qualified for a while, but has bad quality perception. A new upscale product has been designed. I would launch this as a new product even if it shares a lot of the older products characteristics, if I am launching into the same market. If I am launching into a new market segment where there is some knowledge of the older product, but none of the negative imagery, it may be prudent to leverage the older brand.
Example 2: Product B has been launched into a market as a simple, cost effective solution. The company is now contemplating an upscale fully featured much higher priced product. I would (other factors being equal) prefer to launch this as a new premium product with differentiated marketing messages and a clearly distinctive look.